Narrative:

Aircraft had a previous write-up for fire detection loop a problem. On taxi out, we had an intermittent loop 'B' annunciation. Light went out on its own. We reviewed loop light checklist, then took off with all indications normal. Selector in both. At 300 ft, loop light illuminated. Elected to continue to a safe altitude to address problem. At 7000 ft, left engine fire warning. Declared emergency and returned. Warning was intermittent, sometimes no indication, sometimes loop light, sometimes fire warning. Engine parameters all good. Kept engine running. Landed at 142000 pounds. Stopped on runway. Had fire crews confirm no fire, taxied to gate.

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Original NASA ASRS Text

Title: FLC OF S80 HAS FIRE DETECTION LIGHT ACTIVATE AND BECOME INTERMITTENT AFTER TKOF. CLB CONTINUED TO ASSESS SIT THEN RETURN LAND ACCOMPLISHED. EMER DECLARED.

Narrative: ACFT HAD A PREVIOUS WRITE-UP FOR FIRE DETECTION LOOP A PROB. ON TAXI OUT, WE HAD AN INTERMITTENT LOOP 'B' ANNUNCIATION. LIGHT WENT OUT ON ITS OWN. WE REVIEWED LOOP LIGHT CHKLIST, THEN TOOK OFF WITH ALL INDICATIONS NORMAL. SELECTOR IN BOTH. AT 300 FT, LOOP LIGHT ILLUMINATED. ELECTED TO CONTINUE TO A SAFE ALT TO ADDRESS PROB. AT 7000 FT, L ENG FIRE WARNING. DECLARED EMER AND RETURNED. WARNING WAS INTERMITTENT, SOMETIMES NO INDICATION, SOMETIMES LOOP LIGHT, SOMETIMES FIRE WARNING. ENG PARAMETERS ALL GOOD. KEPT ENG RUNNING. LANDED AT 142000 LBS. STOPPED ON RWY. HAD FIRE CREWS CONFIRM NO FIRE, TAXIED TO GATE.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.